Which angles are vertical to eachother​

What constants do you need to add to each of the following quadratic equations to complete the square? 2x2 - 3x = 0 x2 - 8x = 0 2x2 - 11x = 18

Anyone know? will mark brainliest if correct

A, b, c, and d have the coordinates (-8, 1), (-2, 4), (-3, -1), and (-6, 5), respectively. which sentence about the points is true? a. a, b, c, and d lie on the same line. b. and are perpendicular lines. c. and are parallel lines. d. and are intersecting lines but are not perpendicular. e. and are parallel lines.